Shoe manufacturing method and apparatus



@cfi. 6, 1942. L. CRANDELL SHOE MANUFACTURING METHODS AND APPARATUS 1 L e e h 4 S V e e h S 2 Filed June 3, 1941 SOURCE m lizwzm Z. Eran/d955,

TD R.F'- SOURCE 0C1. 6, E. L @RANDELL SHOE MANUFACTURING METHODS AND APPARATUS Filed June 3, 1941 2 Sheets-Sheet 2 [Path/L LauuuZeZZ, W L7 Amway Patented Oct. 6, 1942 SHOE MANUFACTURING METHOD AND APPARATUS Ervin L. Crandell, Vellesley, Mass., assignor to Compo Shoe Machinery Corporation, Boston, Mass., a corporation of Delaware Application June 3, 1941, Serial No. 396,416

12 Claims.

In the apparatus used heretofore, it has been I the practice to provide at least a pair of electrodes, especially made up, for the purpose of producing electrostatic fields for heating the shoe parts. This invention utilizes one or more essential parts of a press for an electrode for the production of the desired electrostatic field.

In one embodiment of the invention, the metal base of a shoe press is utilized as an electrode.

In other embodiments of the invention, water or another liquid is used in pads for exerting pressure upon the shoe parts, and the liquids are connected electrically to high frequency oscillators and used as electrodes for the application of energy from the oscillators to the shoe parts.

Objects of the invention are to simplify, and to reduce the cost of, apparatus utilizing high frequency electrostatic fields for the production of heat in shoe parts.

The invention willnow be described with reference to the drawings, of which:

Fig. 1 is a side elevation of one embodiment, of this invention utilizing the base of a shoe press as an electrode;

Fig. 2 is a side elevation with a portion in section, of another embodiment of this invention in a shoe press and utilizing liquid in an inflatable pad as an electrode;

Fig. 3 is a side elevation with a portion in section of another form of press in which a lower liquid pad is provided and in which the liquid serves as an electrode, and

Fig. 4 is a side elevation of a press with a portion in section, in which opposed liquid filled pads are provided with the liquid serving as opposed electrodes.

In shoe cementing, it is the practice to roughen the bottom of a lasted shoe, and the top of the outsole to be applied, and to coat these parts with an adhesive such as is disclosed in said Pitman patent. Following this, as disclosed in said Smith patent, the shoe assembly is placed in a press; a pad in contact with the outsole is in- I fiated for pressing the shoe parts together and the press moved as by a conveyor, for advancing the shoe assembly to a heating station where heat is produced in the adhesive by a high frequency electrostatic field produced between electrodes placed on opposite sides of the adhesive.

In the embodiment of Fig. l, the shoe press 5 has the metal base 6 on which is placed the inflatable pad l. A shoe 8 having an outsole 9 to be cemented thereto, is seated upon the pad I with the outsole 9 in contact therewith. The last I!) is placed within the shoe 8 as is usual.

The metallic electrode H is placed within the shoe 8 on the upper side of the adhesive. The electrode 1 I may be a metal bottom on the last in as disclosed in said Smith patent, or may be an electrode within the shoe body, as disclosed in my copending application, Serial No. 387,823.

The metal pin l2 has its upper end in contact with the metal lining 13 in the last jack-pin hole [4, the upper portion of the lining 13 being in contact with the metallic plate [5 on the heel post IS.

The heel post I6 is a block of insulating material of the porcelain type and serves to insulate the electrical conductor bolt I! which extends through an opening [8 in the press 5, from the press 5. The bolt II at its lower end is in contact with the plate l5 and at its upper end is in contact with the plate [9. The insulator 20 insulates the plate 19 from the press 5.

The electrical conductor 2| is mounted from the insulators 22 attached to the press, and is connected to the upper end of the bolt I! and serves to connect through the bolt H, the plate [5, the lining l3 and the pin l2, the electrode H to one side of the circuit of a high frequency electrical source such, for example, as the one disclosed in said Smith patent.

The other side of the circuit of the high frequency electric source is connected by the conductor 23 to the metal press base 6 at 24 and to ground.

A high frequency electrostatic field is set up between the electrode ll and the base 6, the energy from this field causing heat to be produced in the adhesive between the shoe parts as explained in said Pitman patent. I

The pad 7 of the press 5 of Fig. 1 is intended to be inflated with air as disclosed in said Smith patent.

The embodiment of Fig. 2 is similar to that of Fig. 1 except that the pad 1 thereof, is intended to be inflated during the inflation cycle, through the tube 25 with an electrically conductive liquid which may, for example, be water treated with a suitable salt for increasing its con-' ductivity.

The tube is connected by the conductor 26 to the press base 6 and to the conductor 23 and to ground.

The pad I of Fig. 2 preferably contains the metallic member 28 which may be a wire mesh connected electrically to the tube 25 and which By grounding the base*6 of Fig. 2 to the tube 25, any stray capacity between the pad I and the base 6 which would result in electrical losses, are eliminated.

The embodiment of Fig. '3 illustrates a form of press which may be used for cementing plies of material such, for example as loath, together. The press 30 has the hollow metal base 3! which contains the electrically conductive liquid 32. The base 3| has the-upper flexible diaphragm 33 which for example, may be rubber.

The metal plate 34 disposed above the diaphragm 33 is attached to the electric insulator 35 in the upper portion of which is formedthe ball socket 36 for up and down movement of the plate through adjustment of the screw 31 by the hand wheel 38.

The plate 34 serves as one of two opposed electrodes, and is connected by the'lead 38 to the high frequency oscillator 39. The base 3| is connected by the lead 46 to the oscillator 39 and serves as the other of the opposed electrodes.

The work layers 4| and 42 with the adhesive 43 therebetween are pressed together between the plate 34 and the diaphragm 33 and a high frequency electrostatic field is set up between the plate 34 and the surface of the liquid 32, which field produces heat in the adhesive 43.

The press 44 of Fig.4 is designed for molding articles such for example, as a shoe outsole 45 t against a form 46. The hollow metal base '35 has the upper flexible diaphragm 47 and is filled with the electrically conductive liquid 48.

The hollow metal box 49 has the lower flexible diaphragm 56 and is filled with the electrically conductive liquid 5|. The electric insulator 52 is attached to the box 49 and contains the ball socket 53 for up and down movement of the box 49 through adjustment of hand wheel 55.

The liquid in the box 49 serves as the upper of a pair of opposed electrodes and may be connected by the lead 56 to a suitable high frequency oscillator. The liquid in the base 46 serves as the lower of the opposed electrodes and may be connected by the lead 51 to an oscillator.

The form 46 may be for example, a form for molding outsoles for women's shoes having high heels. The layer of material 45 may therefore be a leather outsole which is pressed by the dia- 2- phragm of the box 49 against the form.

The upper and lowerdiaphragms being flexible, adapt themselves to the shape of the form and to the desired shape of the outsole.

A high frequency electrostatic field is prothe screw 54 by the said pad for inflating same, means forming an duced between the surfaces of the liquid in the base 46 and in the box 49 when a high frequency oscillator is connected as described and the outsole 45 is heated by the action of the field causing it to adapt itself under the pressure and the heat, to the shape of the form.

In the appended claims, the articles or materials referred to as being heated are articles or materials which have dielectric properties which will enable heat to be generated therein when exposed to the infillence'of electrostatic fields.

While embodiments of the invention have been described for the purpose of illustration, it should be understood that the invention is not limited to the exact apparatus and arrangements of ap -of the output circuit of a high frequency electric source to said electrode and to said liquid, and means for moving said electrode towards said liquid with said assembly therebetween.

2. Apparatus for cementing an outsole to a shoe, comprising a shoe press; means in said press comprising an inflatable pad containing an electrically conductive liquid for supporting a shoe assembly thereon; means forming an electrode within said assembly, and means for connecting opposite sides of the output circuit of a high frequency electric source to said electrode and to said liquid.

3. Apparatus for cementing an outsole to a shoe, comprising a shoe press; means including an inflatable pad in said press for supporting 'a shoe assembly thereon, and with said pad in contact with the lower side of the outsole of said assembly, means for admitting an electrically conductive liquid into said pad for inflating same,

means forming an electrode within said assembly, and means for connecting opposite sides of the output circuit of a high frequency electric source to said electrode and to said liquid.

4. Apparatus for cementing an outsole to a shoe, comprising a shoe press having a metal base; means including an inflatable pad in said press for supporting a shoe assembly thereon, and with said pad in contact with the lower side of the cutsole of said assembly, means for admitting an electrically conductive liquid into electrode within said assembly; means for connecting opposite sides of the output circuit of a high frequency electric source to said electrode and to said liquid, and means for electrically connecting said base to said liquid, and to said liquid admitting means.

5. Apparatus for heating an article, comprising a press base containing an electrically conductive liquid; a flexible diaphragm secured to said base to confine said liquid; an electrode spaced from but aligned with, said diaphragm; means for moving said electrode and said diaphragm towards each other, and means for connecting a high frequency electric source to said liquid and to said electrode.

7. A press forheating an article, comprising a press base having an electrically conductive fluid confined therein by a flexible diaphragm; a pressing member containing an electrically conductive fluid; means for urging said pressing member towards and away from said diaphragm,

and means for connecting opposite sides of a high frequency electrical source to said base and to said pressing member.

8. A press for heating an article, comprising opposed receptacles filled with electrically conductive liquids; adjacent sides of said receptacles comprising flexible diaphragms, means for moving said receptacles towards each other for pressing an article to be heated therebetween, and means for connecting the opposite sidesof a. high frequency electric source to the liquids in said receptacles.

9. A press for heating an article, comprising a press base having an electrically conductive fluid confined therein by a flexible diaphragm; a pressing member containing an electrically conductive fluid confined therein by a flexible diaphragm; means for urging said diaphragms towards each other for pressing the article to be heated therebetween, and means for connecting opposite sides of a high frequency electrical source to said base and to said pressing member.

10. A press for heating an article, comprising oDDpsed receptacles filled with electrically conductive liquids; adjacent sides of said receptacles comprising flexible diaphragms; a form for positioning on one of said diaphragms; means for moving said receptacles towards each other for pressing an article to be heated against said form, and means for connecting the opposite sides of a high frequency electric source to the liquids in said receptacles.

11. A method of molding articles, comprisingv placing an article on a form complemental to the shape desired; pressing the article against one side of said form with a pad having a flexible surface in contact therewith, and containing an electrically conductive liquid; placing an electrade at the other side of said form, and while the article is so pressed, setting up an electrostatic field between said liquid and said electrode.

12. A method of molding articles, comprising placing an article on a form complemental to the shape desired; pressing the article and the form together with pads having flexible surfaces in contact therewith, and containing electrically conductive liquids, and setting up electrostatic fields between said liquids.

ERVIN L. CRANDELL. 

